Aircraft construction



J. A. STEINMETZ.. AIRCRAFT CONSTRUCTION. APPLICATION FILED JAN. 8T 1918.

Patented M31'. 9, 1920.

3 Q C o@ Q @f STATES PATENT oFFIcE.`

JosnPH A. sTEINME'rz, or PHILADELPHIA, PENNSYLVANIA.

` `AIRCRAFT CONSTRUCTION.

Specification of Letters Patent.

Patented. Mar. 9, i920.,

Application led January 8, 1918. Serial No. 210,888.

To all 'whom z't may concern to combine lightness and strength and topromote rapidity of manufacture, While using, large laboratcomparatively low wages.

hese ends are sought by making thev framework -of wings, planes, .orother de! sired members by pressing plastic material, for example,papier mch, reinforced if desired, into proper forms, and when desiredincorporating therein strong threads of `metal or.- other material.

In the accompanying drawings,

Figure 1 is a, plan vlew of the body portion of an. aeroplane wing orlan y Fig. 2 is a c ross section o the plane of 1. ig. 3 shows aslightly modified construction.`

Fig. 4 is a cross sectional view of the structure of Fig. 3.

' F ig. 5 is Aa similarcross sectional view showing a furthermodification.

Fig. 6 shows an enlar ed cross section of a portion of `a structureaving ribs on both faces of the body sheet.

. Fi 7 is a cross Sectional view illustratingt e use of a smooth sheetof pressed mateial having on one face canvas receiving r1 s.

Fig. 8 illustrates the use of a central web having an unequal number ofribs on its two faces.

Fig. 9 shows a portion of a modified wing framework.

,Fi 10 is a perspective view illustratin a deslrable form f reinforcedmember suc asis shown in Fig. 9. y

In these figures, 15 designates the body of a. 'supporting lane ofprimarily plastic material press to form a sheet 16 havin lon one 'faceintegral intersecting ribs 17 an provided withweight-reducingopeningslS. Along one margin the sheet is preferably `ening, preferablyeachconnecting we and with wires 36, or

fixed toY a Wood member 19, andthe ribs preferably decrease in height as.their distance from this member increases. To the margins of the ribs asheet 2() ofcanvas or the like is secured, usually by-nails driventhrough the canvas into the ribs.

Figs.. 3 and 4 omit the member 19 and show lnstead a light wood strip 21passed through the transverse ribs 22.

Fig. 5 shows a body sheet 23 having nonregistering ribs 24 on theA freeedges of which flat wood strips 25 are fiXed,-toreceive canvassheets 26.

In the form of Fig. 6 `the ribs register and the wood strips 25 areomitted.

Fig. 7 illustrates a continuousl imperforate sheet having on one faceribs 28 to which canvas 29 -is nailed.

p In some' cases, 'as shownin Fig. 8, a con` r tinuous sheet 30 isprovided with ribs 31 and on the opposite face with more numerous ribs32. I

A very rapidly made and assembled framework is shown in Fig. 9, where 33represents duplicate transverse papier mch wing ribs readily pressed toform in suitable dies. Theseare properlyy spaced parallel to eachotherand connected by longitudinal strips 34 passing through all the rib-s.AThe' lribs are preferably of I-beam cross section,

as lshown in Fig. v10, and where y great strength is-desired areprovided with a stifferforated, plate l35 -in the like, in the webstransverse to thel planes of the connectin webs.

When the initially plastic material contains throughout its massnumerous strong threads of grass, common textile material, or metal, ithas great strength for a given weight, pressed forms ive stiffness, andwhen dies are once ma e, any number of duplicate parts can be producedwith great rapidity and with very little skill, no care# l ful littmgand connection by expensive mechanics bein necessary.

What lI c aim is: 1. In a supporting plane for aircraft, th

combination with a pressed pulp sheet hav ing on its face a series ofintegral ribs, of an approximately parallel sheet secured to the edgesof said ribs, substantially as set forth.

2; In a supporting p'lane for aircraft, the combination. with a pressedpulp sheet having on its face a series of integral ribs intersected bythe ribs of a second series of like height, of a fabric sheet secured tothe marginal faces' of the ribs, si'lbstantially as set forth.

3. In a supporting plane for aircraft, the combination with a papier mchsheet having on both lfaces intersecting integral ribs and provided Withopenings in the seyeral spaces surrounded by the ribs, and thin sheetsof different material secured to the first mentioned.

l. A structural unit for alrcraft consisting of a rib of primarilyplastic material of 15 I-beam cross section having in its marginal Webreinforcing Wires and in its connecting` Web a stiening plate.

In testimony whereof I hereunto atlix my signature.

JOSEPH A. STEINMETZ.

